An electrical power converter, which is configured to perform an electrical power conversion with an electricity storage apparatus such as a secondary battery, a capacitor and the like by changing a switching state of switching element, is known. Especially, the electrical power converter which is configured to perform the electrical power conversion with a plurality of electricity storage apparatuses is proposed, as disclosed in a Patent Literature 1. The electrical power converter like this has three or more switching elements which are electrically connected in series as the switching elements which are used to perform the electrical power conversion with the plurality of electricity storage apparatuses. For example, the electrical power converter for a vehicle, which moves by using the electrical power outputted from two electricity storage apparatuses, has four switching elements which are electrically connected in series as the switching elements which are used to simultaneously perform the electrical power conversion with two electricity storage apparatuses.